TY - JOUR TI - Preparturient diabetogenesis in primiparous gilts AU - Schaefer, A. L. AU - Tong, A. K. W. AU - Sather, A. P. AU - Beltranena, E. AU - Pharazyn, A. AU - Aherne, F. X. T2 - Canadian Journal of Animal Science AB - The objective of the present study was to examine gestational diabetogenic effects in lean gilts and the influence that dietary protein may have on glucose tolerance, reproductive performance, maternal insulin and progesterone levels. Twenty-six Lacombe gilts (14 control, 12 treated) and 229 neonate offspring were examined. During gestation all gilts received a 13% crude protein balanced diet on the basis of body weight. The treated animals received the same diet plus an additional 1.3 g kg −1 body weight d −1 of casein starting on day 1 postcoitus. No differences in litter size or birth weight between treatments were observed. However, the proportion of mummified or still-birth fetuses, while within a normal range, tended to be higher (P < 0.10) in control (1.64 ± 0.43 per litter) than in treated pigs (0.58 ± 0.46). In addition, the muscle protein concentration in the neonatal offspring of treated gilts (91.3 ± 0.35 mg g −1 ) tended to be higher (P = 0.15) than that seen in the control animals (88.7 ± 0.34 mg g −1 ). All pregnant gilts, irrespective of treatment, displayed a degree of diabetogenesis two weeks prepartum (P ≤ 0.05). However, no differences in blood insulin or progesterone levels were observed between treatments. The data suggest that protein supplementation to the dam may slightly retard gestational onset diabetogenic effects but has only moderate effects on fetal outcome. Key words: Diabetogenesis, lean gilts, dietary protein DA - 1991/3/1/ PY - 1991/3/1/ DO - 10.4141/cjas91-008 VL - 71 IS - 1 SP - 69-77 J2 - Can. J. Anim. Sci. LA - en OP - SN - 0008-3984 1918-1825 UR - http://dx.doi.org/10.4141/cjas91-008 DB - Crossref ER - TY - JOUR TI - Effects of pre- and postpubertal feeding on production traits at first and second estrus in gilts. AU - Beltranena, E AU - Aherne, F X AU - Foxcroft, G R AU - Kirkwood, R N T2 - Journal of Animal Science AB - The effects of feeding level on body weight (BW), lifetime growth rate, backfat thickness (BF), fatness (BF/BW) and ovulation rate at first (puberty) and second estrus were examined in 145 gilts. From 47.2 kg until puberty, gilts were fed 2.0 kg/d (L) or had ad libitum access to feed (H). From puberty to second estrus, the feed allowance of one-half of the L gilts was increased to 2.8 kg/d. Flush-feeding only normalized ovulation rate (OR) to that observed in gilts with ad libitum access to feed. At puberty, a quadratic negative relationship between lifetime growth rate and age indicated that age at puberty was minimum at a growth rate of less than or equal to .60 kg/d. Thereafter, age at puberty became independent of, or possibly positively related to, lifetime growth rate. Gilts with higher lifetime growth rate also were heavier and fatter at puberty. It was concluded that puberty may have been attained when a certain BF or fatness was achieved, because growth rate of restricted-fed gilts and quickly growing gilts with ad libitum access to feed may have been associated with reduced fat deposition. Hence, maximizing growth rate in replacement gilts does not hasten the attainment of puberty. Growth rate may be manipulated by feed restriction, in order to attain a target BW at boar stimulation (approximately 90 kg), which would coincide with a minimum age (approximately 155 d) and BW at puberty (approximately 97 kg). Nutritional flushing during the first estrous cycle then could be used to normalize OR at mating at second estrus of gilts that were restricted-fed when prepubertal. DA - 1991/// PY - 1991/// DO - 10.2527/1991.693886x VL - 69 IS - 3 SP - 886 LA - en OP - SN - 0021-8812 UR - http://dx.doi.org/10.2527/1991.693886x DB - Crossref ER - TY - JOUR TI - Endocrinology of nutritional flushing in gilts AU - Beltranena, E. AU - Foxcroft, G. R. AU - Aherne, F. X. AU - Kirkwood, R. N. T2 - Canadian Journal of Animal Science AB - As part of a nutritional flushing study, the endocrine status of gilts was compared to gain further knowledge of the mechanism(s) that mediate the restoration of ovulation rate. From 45.3 kg BW to puberty, 42 gilts were fed 2.0 kg d −1 (L) or ad libitum (H). From puberty to second estrus, one-half of the L gilts had their feed allowance increased to 2.8 kg d −1 (LH). Gilts in the H group continued to be fed ad libitum (HH). Gilts in the LH and H groups showed a greater increase in ovulation rate between first and second estrus than LL gilts (P < 0.05). Based on sampling every 4 h through the peri-estrous period of 28 gilts, feeding level did not affect mean plasma follicle-stimulating hormone (FSH), luteinizing hormone (pLH), estradiol-17β or progesterone concentrations (P > 0.05). During the follicular phase, however, LH and HH gilts had not only a greater proportion of samples > 1 ng mL −1 but also showed an increased mean pLH daily sample variance compared with LL gilts (P < 0.05). The latter parameters were interpreted as indicators of an increased frequency of episodic pLH release. Furthermore, HH gilts had greater (P < 0.05) plasma insulin concentrations through the peri-estrous period and greater insulin-like growth factor I (IGF-I) concentrations during the pLH-surge period than LL gilts. These results confirm that increased plasma insulin may be an important metabolic cue, which in an independent or synergistic action with gonadotropins and IGF-I mediates the ovulatory response to flush-feeding. Key words: Gilt, flushing, ovulation, gonadotropins, insulin, IGF-I. DA - 1991/12/1/ PY - 1991/12/1/ DO - 10.4141/cjas91-128 VL - 71 IS - 4 SP - 1063-1071 J2 - Can. J. Anim. Sci. LA - en OP - SN - 0008-3984 1918-1825 UR - http://dx.doi.org/10.4141/cjas91-128 DB - Crossref ER - TY - CONF TI - Effects of inoculants of lactic acid bacteria upon aerobic stability and fermentation quality of high moisture ear corn, and upon its subsequent utilisation by beef steers AU - Phillip, L.E. AU - Fellner, V. T2 - 41st Annual Meeting CSAS C2 - 1991/// C3 - CSAS Proceedings CY - Fredericton, New Brunswick DA - 1991/// PY - 1991/// SP - 3 ER - TY - CHAP TI - Analysis and quality control of feedstuffs AU - Yang, S. AU - Ding, J.L. AU - Zhu, Y.Q. AU - Lin, Xi AU - Gong, L.M. T2 - National teaching materials for institution of higher learning, colleges and universities PY - 1991/// PB - BAU press ER - TY - JOUR TI - Development of a renal adaptive response assay as a measure of taurine bioavailability in adult cats AU - Glass, E.N. AU - Odle, J. AU - Baker, D.H. AU - Czarnecki-Maulden, G.L. T2 - FASEB Journal DA - 1991/// PY - 1991/// VL - 5 SP - A591 ER - TY - CONF TI - Urinary excretion of taurine (TAU) as a function of TAU intake: Potential for estimating TAU bioavailability in the adult cat AU - Odle, J. T2 - Waltham Symposium on Taurine and Cat Nutrition C2 - 1991/// CY - Orange Beach, Alabama DA - 1991/// PY - 1991/10/8/ ER - TY - MGZN TI - Nutrient allowances for swine AU - Easter, R.A. AU - Odle, J. AU - Baker, D.H. T2 - Feedstuffs DA - 1991/// PY - 1991/// VL - 63 SP - 38–44 ER - TY - MGZN TI - Dosing baby pigs improves survival AU - Odle, J. T2 - National Hog Farmer DA - 1991/// PY - 1991/// VL - 36 SP - 40–42 M1 - Swine Research Review ER - TY - JOUR TI - Does supplemental carnitine affect octanoate oxidation in colostrum-deprived newborn pigs? AU - van Kempen, T.A.T.G. AU - Odle, J. T2 - FASEB Journal DA - 1991/// PY - 1991/// VL - 6 SP - A1382 ER - TY - SOUND TI - Urinary excretion of taurine as a function of taurine intake: Potential for estimating taurine bioavailability in the adult cat AU - Odle, J. DA - 1991/// PY - 1991/// ER - TY - JOUR TI - Effects of emulsification on the utilization of medium-chain triglycerides (MCT) by neonatal piglets AU - Wieland, T.M. AU - Odle, J. T2 - FASEB Journal DA - 1991/// PY - 1991/// VL - 5 SP - A1306 ER - TY - JOUR TI - Maximizing Gluten Feed in Corn Silage Diets for Dairy Cows AU - Fellner, V. AU - Belyea, R.L. T2 - Journal of Dairy Science AB - Abstract Corn silage-based diets containing 20, 40, or 60% (DM basis) corn gluten feed were fed to 72 lactating cows to determine intake, milk yield, and milk composition. These diets plus a control (no corn gluten feed) were fed to four ruminally fistulated cows to determine digestibility and ruminal ammonia and VFA concentrations. Milk yields were significantly lower for cows fed the diet with 60% corn gluten feed, but when adjusted by covariate, milk yield was not different among diets. Milk protein percentage was greater for cows fed the 40 and 60% corn gluten feed diets. In the digestion trial, increased corn gluten feed led to decreased DM digestibility and decreased ruminal acetate concentration but did not affect N, NDF, ADF, or starch digestibilities. Ruminal ammonia and pH were unaffected. Net energy estimates for the diets were low relative to book values, suggesting significant depression in digestibility. Compared with conventional diets, NDF intake was high; this suggests that cows compensated for lower digestibility with increased DM intake. Diets containing up to 60% of DM as dry corn gluten feed were acceptable for dairy cows. DA - 1991/3// PY - 1991/3// DO - 10.3168/jds.s0022-0302(91)78249-0 VL - 74 IS - 3 SP - 996-1005 J2 - Journal of Dairy Science LA - en OP - SN - 0022-0302 UR - http://dx.doi.org/10.3168/jds.s0022-0302(91)78249-0 DB - Crossref KW - BY-PRODUCT FEED KW - LACTATING COW KW - DIGESTIBILITY ER - TY - JOUR TI - Clinical Challenge: Case 2 AU - Bradley, T.A. AU - Carpenter, J.W. AU - Muñana, K.R. AU - Douglass, J. T2 - Journal of Zoo and Wildlife Medicine DA - 1991/// PY - 1991/// VL - 22 SP - 505–506 ER - TY - JOUR TI - What is your diagnosis? AU - Muñana, K.R. T2 - Progress in Veterinary Neurology DA - 1991/// PY - 1991/// VL - 2 SP - 213–214 ER - TY - JOUR TI - Postnatal age and the metabolism of medium- and long-chain fatty acids by isolated hepatocytes from small-for-gestational-age and appropriate-for-gestational-age piglets AU - Odle, J. AU - Benevenga, N.J. AU - Crenshaw, T.D. T2 - Journal of Nutrition DA - 1991/// PY - 1991/// VL - 121 IS - 5 SP - 615-621 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0025800975&partnerID=MN8TOARS ER - TY - JOUR TI - Utilization of medium-chain triglycerides by neonatal piglets: Chain length of even- and odd-carbon fatty acids and apparent digestion/absorption and hepatic metabolism AU - Odle, J. AU - Benevenga, N.J. AU - Crenshaw, T.D. T2 - Journal of Nutrition DA - 1991/// PY - 1991/// VL - 121 IS - 5 SP - 605-614 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0025818442&partnerID=MN8TOARS ER - TY - JOUR TI - Research note: bioavailability of copper in cupric oxide, cuprous oxide, and in a copper-lysine complex. AU - Baker, D.H. AU - Odle, J. AU - Funk, M.A. AU - Wieland, T.M. T2 - Poultry science DA - 1991/// PY - 1991/// VL - 70 IS - 1 SP - 177-179 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0026036708&partnerID=MN8TOARS ER - TY - JOUR TI - EFFECTS OF PROTEIN LEVEL AND FORAGE SOURCE ON MILK-PRODUCTION AND COMPOSITION IN EARLY LACTATION DAIRY-COWS AU - ZIMMERMAN, CA AU - RAKES, AH AU - JAQUETTE, RD AU - HOPKINS, BA AU - CROOM, WJ T2 - JOURNAL OF DAIRY SCIENCE AB - Twenty multiparous and 12 primiparous Holstein cows were assigned at calving to one of three grass hay-based diets containing either 14, 18, or 22% CP or an alfalfa hay-based diet containing 22% CP to examine the effect of protein level and forage source on milk yield and composition. The diets contained 23% ADF during wk 1 to 4 postpartum, which was lowered to 11% for wk 5 to 12 postpartum. Cows fed the 18 and 22% CP grass-based diets produced higher yields of milk, 4% FCM, fat, protein, and SNF than those fed the 14% CP diet during the high fiber period. In addition, cows fed the 22% CP grass-based diet had higher milk fat tests than those fed the 14% CP diet during the high fiber period, due primarily to an increase in short-chain fatty acid synthesis. Milk fat depression was more severe when cows were changed to low fiber diets while fed the 22% CP alfalfa-based diet than when fed the 22% CP grass-based diet. Depression in milk fat content was 15.0, 17.0, 15.6, and 27.0% for 14, 18, and 22% CP grass-based and 22% CP alfalfa-based diets, respectively. Cows receiving the 18 and 22% CP grass-based diets exhibited higher blood NEFA during the high fiber feeding period than those fed the 14% CP diet. After fiber was lowered, changes in rumen acetate:propionate ratios were unaffected by treatment. Lowering fiber level resulted in an increased milk CP percentage regardless of treatment. Grass hay appeared to be more effective than alfalfa hay in preventing depression in milk fat test upon the change to a low fiber diet. DA - 1991/3// PY - 1991/3// DO - 10.3168/jds.S0022-0302(91)78247-7 VL - 74 IS - 3 SP - 980-990 SN - 0022-0302 KW - CRUDE PROTEIN KW - MILK FAT DEPRESSION KW - LOW FIBER ER - TY - JOUR TI - EVALUATION OF A BACTERIAL FEATHER FERMENTATION PRODUCT, FEATHER-LYSATE, AS A FEED PROTEIN AU - WILLIAMS, CM AU - LEE, CG AU - GARLICH, JD AU - SHIH, JCH T2 - POULTRY SCIENCE AB - Feeding trials were designed to evaluate the nutritive value of feathers treated by a feather-degrading bacterium, Bacillus licheniformis (Strain PWD-1). An initial experiment compared feathers that had been treated under aerobic or anaerobic conditions with untreated feathers as 25% of the feed protein in the diet. The test diets were fed to growing broiler chicks from Day 6 through Day 21 posthatch. The anaerobically fermented product, feather-lysate, resulted in improved growth responses of 6.9 and 19.3% over the aerobic- and nonbacterial-treated feather feed products, respectively, but 6.4% less than a standard com-soybean-based diet In a subsequent experiment, 3 or 6% of feather-lysate, untreated feathers, and commercial feather meal were fed to chicks on a basal diet containing only 10% protein. The linear growth response slopes were compared with the slope resulting when chicks were fed diets containing soybean protein in graded levels from 10 to 19% of the total feed. Feather-lysate supplemented with lysine, methionine, and histidine produced a growth curve identical to that of soybean meal. Commercial feather meal supported an improved growth rate over the untreated feathers but significantly less than feather-lysate. These results indicate that the anaerobic fermentation of feathers offers a potential new process for feather waste treatment to provide a nutritious feed protein. DA - 1991/1// PY - 1991/1// DO - 10.3382/ps.0700085 VL - 70 IS - 1 SP - 85-94 SN - 0032-5791 KW - FEATHER KW - BACTERIAL FERMENTATION KW - FEATHER-LYSATE KW - PROTEIN KW - NUTRITION ER - TY - JOUR TI - RELATIONSHIPS AMONG MILK-YIELD, METABOLISM, AND REPRODUCTIVE-PERFORMANCE OF PRIMIPAROUS HOLSTEIN COWS TREATED WITH SOMATOTROPIN AU - MORBECK, DE AU - BRITT, JH AU - MCDANIEL, BT T2 - JOURNAL OF DAIRY SCIENCE AB - Thirty-two primiparous Holsteins were assigned to receive 0, 5.15, 10.3, or 16.5 mg/d recombinant bST. Treatment began between 28 and 35 d postpartum and continued until 60 d prior to next expected calving or 400 d postpartum. Metabolic hormones and metabolites were measured in blood weekly during the first 10 wk of treatment, and progesterone was measured in milk twice weekly to assess ovarian activity until conception. Milk production (305 d, actual) was 8350 +/- 562, 8348 +/- 515, 9571 +/- 515, and 9070 +/- 515 for cows given 0, 5.15, 10.3, or 16.5 mg/d and did not differ statistically. Insulin, glucose, NEFA and blood urea nitrogen were not influenced by dose of bST. However, insulin-like growth factor-I increased linearly with dose of bST. Days from parturition to first detected estrus, days open, and services per conception did not differ among groups; however, days from parturition to first service increased with dose of bST. Rate of detection of estrus decreased with dose of bST, resulting in a longer interval to first insemination. The lower rate of detection of estrus in bST-treated cows may have been associated with reduced expression of estrus. Additional statistical analyses were conducted to determine the relationship between metabolism, milk production, and reproduction over all doses of bST. There was a negative correlation between 305-d milk yield and glucose (r = -.44) and insulin (r = -.46) concentrations during 30 to 100 d postpartum. In stepwise regression analyses, insulin accounted for 21% of the variance in 305-d milk yield. Glucose and NEFA accounted for 18% of the variance in days open, and there was a negative correlation (r = -.32) between glucose and days open. Days open and milk production were not correlated. DA - 1991/7// PY - 1991/7// DO - 10.3168/jds.s0022-0302(91)78388-4 VL - 74 IS - 7 SP - 2153-2164 SN - 0022-0302 KW - PRIMIPAROUS DAIRY CATTLE KW - SOMATOTROPIN KW - REPRODUCTION ER - TY - JOUR TI - Protection of agammaglobulinemic piglets from porcine rotavirus infection by antibody against simian rotavirus SA-11 AU - Lecce, J. G. AU - Leary, H. L., Jr. AU - Clare, D. A. AU - Batema, R. P. T2 - Journal of Clinical Microbiology DA - 1991/// PY - 1991/// VL - 29 IS - 7 SP - 1382 ER - TY - JOUR TI - DURATION OF ESTROUS CYCLES SUBSEQUENT TO 2 INJECTIONS OF PROSTAGLANDIN-F2-ALPHA GIVEN AT A 14-DAY INTERVAL IN NONLACTATING HOLSTEIN COWS AU - MORBECK, DE AU - TYLER, HD AU - BRITT, JH T2 - JOURNAL OF DAIRY SCIENCE AB - Data from previous experiments in our laboratory indicated that estrous cycles following synchronization with two injections of prostaglandin F2 alpha often averaged more than 21 d. To investigate whether this could be an effect of prostaglandin F2 alpha, 54 mature heifers and nonlactating Holstein cows were used in a crossover experiment in which estrous cycles either occurred spontaneously or followed two injections of prostaglandin F2 alpha at a 14-d interval (induced estrus). One estrous cycle of each type was recorded for each animal. Blood samples were collected twice weekly for analysis of progesterone. Cattle were observed twice daily for estrus with the aid of tail chalking and an androgenized cow. Estrous cycles following induced estrus were longer than those following spontaneous estrus (24.2 vs. 22.7 d). Ninety-two percent of the cycles following spontaneous estrus were 17 to 25 d in duration compared with 71% of the cycles following induced estrus. If the first prostaglandin F2 alpha was given when progesterone was greater than 1 ng/ml, the estrous cycle following treatment was longer than if the first prostaglandin F2 alpha was given when progesterone was less than 1 ng/ml (26.0 vs. 22.6 d). This experiment demonstrates that two injections of prostaglandin F2 alpha increase the incidence of estrous cycles greater than 25 d. Stage of the estrous cycle at time of the first injection of prostaglandin F2 alpha may contribute to this effect. DA - 1991/7// PY - 1991/7// DO - 10.3168/jds.s0022-0302(91)78407-5 VL - 74 IS - 7 SP - 2342-2346 SN - 0022-0302 KW - REPRODUCTION KW - ESTROUS CYCLE KW - PROSTAGLANDIN ER - TY - JOUR TI - BODY-TEMPERATURE AND RESPIRATORY RATE OF LACTATING DAIRY-CATTLE UNDER FIELD AND CHAMBER CONDITIONS AU - LEGATES, JE AU - FARTHING, BR AU - CASADY, RB AU - BARRADA, MS T2 - JOURNAL OF DAIRY SCIENCE AB - A coordinated field and chamber experiment assessed breed, sire, and cow differences in body temperatures and respiratory rates. During each of 4 yr, 10 lactating Ayrshire, Guernsey, Holstein, and Jersey cows, 40 animals per yr, were observed in the field on 10 d when the air temperature approached 32 degrees C. For the first 3 yr, each cow also was exposed in a controlled atmospheric chamber at 40 degrees C and 34 mm Hg vapor pressure. Significant breed differences were found for body temperature and respiratory rate. The order of tolerance to hot conditions was Jersey, Guernsey, Ayrshire, and Holstein both in the field and chamber. Significant sire differences, interpreted as genetic, were found for the field measures but not in the chamber. Repeatability of individual field observations for a cow on different days in a year ranged from .38 to .55. Correlations between the average of 10 observations for a cow in the field during a year and the chamber evaluation were positive but lower than the repeatability values. Correlations of ambient temperature with body temperatures and respiratory rates were highest; those for radiation were next, followed by vapor pressure and air movement. DA - 1991/8// PY - 1991/8// DO - 10.3168/jds.S0022-0302(91)78426-9 VL - 74 IS - 8 SP - 2491-2500 SN - 0022-0302 KW - BODY TEMPERATURE KW - RESPIRATORY RATE ER - TY - JOUR TI - Protective effect of decoquinate for preruminant Holstein calves in relation to serum IgG AU - Ramsey, H. A. AU - Whitlow, L. W. AU - McDaniel, B. T. AU - Ducharme, G. A. T2 - Journal of Dairy Science DA - 1991/// PY - 1991/// VL - 74 SP - 273 ER - TY - JOUR TI - Effect of growing corn and sorghum in alternate rows on silage feeding value for milking cows AU - Rakes, A. H. AU - Burns, J. C. AU - Whitlow, L. W. T2 - Journal of Dairy Science DA - 1991/// PY - 1991/// VL - 74 SP - 298 ER - TY - JOUR TI - VARIATION AMONG DONOR FEMALES IN MAMMALIAN PREIMPLANTATION EMBRYO RESEARCH AU - POMP, D AU - EISEN, EJ T2 - THERIOGENOLOGY AB - Data from two investigations involving preimplantation mouse embryo survival rates were analyzed by statistical methods which considered (Analysis I) or ignored (Analysis II) variation among-donor females. The first investigation studied in vitro development of zygotes in two culture media. Embryos from each donor female were randomly allocated to treatments. Analysis I utilized donor female as a block, removing among-donor female variation from the mean-square error. Analysis II ignored this variation, as if embryos from all donor females were pooled prior to random allocation to treatment. Media effects were large in both cases, and interpretation of results did not differ among analyses for an outbred stock or for an outbred × inbred cross. However, level of significance was consistently more extreme in Analysis II than in Analysis I. The second investigation studied genotypic responses in development of eight-cell embryos following cryopreservation. Survival rate was measured per donor female within genotype. Analysis I utilized donor females nested within genotype as the error term. Analysis II again utilized categorical pooling of data, ignoring donor females. In several cases, genotype differences and interaction effects were significant in Analysis II but not in Analysis I. Interpretation of results was dependent upon type of analysis. Consideration of among-donor female variation consistently yielded conservative tests of hypotheses relative to analyses which ignored this source of variation. Failure to consider among-donor female variation may lead to improper hypothesis testing, thus increasing the risk of false rejection of null hypotheses (Type-I error). DA - 1991/6// PY - 1991/6// DO - 10.1016/0093-691X(91)90367-M VL - 35 IS - 6 SP - 1209-1224 SN - 0093-691X KW - EMBRYOS KW - EXPERIMENTAL DESIGN KW - STATISTICAL ANALYSIS ER - TY - JOUR TI - SURVIVAL OF EARLY PREIMPLANTATION PORCINE EMBRYOS AFTER COCULTURE WITH CELLS PRODUCING AN AVIAN RETROVIRUS AU - JIN, DI AU - PETTERS, RM AU - JOHNSON, BH AU - SHUMAN, RM T2 - THERIOGENOLOGY AB - To determine the relative survival of porcine embryos after co-culture with cells producing an avian retrovirus, four-cell stage embryos were obtained from sows following synchronization with altrenogest and superovulation with gonadotropins. These embryos were randomly assigned to the following treatments: no manipulation (zona-intact); zona removed with acidified Tyrode's solution (zona-free); and zona removed followed by co-culture with D-17 canine cells producing an avian retrovirus vector derived from spleen necrosis virus (zona-free + co-culture). The survival rates of four-cell stage embryos to morulae or early blastocysts during a 48-h culture period were 93.3, 80.0 and 57.7% in zona-intact, zona-free and zona-free + co-culture groups, respectively. Following embryo transfer, the development of embryos to fetuses at six weeks of gestation was 37.5, 30.0 and 11.7% in zona-intact, zona-free and zona-free + co-culture groups. These results indicate that early preimplantation porcine embryos can develop to apparently normal fetuses following co-culture with cells producing a retrovirus, and the feasibility of this method for retrovirus-mediated gene transfer in pigs was demonstrated. DA - 1991/3// PY - 1991/3// DO - 10.1016/0093-691X(91)90448-M VL - 35 IS - 3 SP - 521-526 SN - 1879-3231 KW - PIG KW - EMBRYO KW - RETROVIRUS KW - COCULTURE KW - EMBRYO TRANSFER ER - TY - JOUR TI - Impairment of follicular development by intra-ovarian infusion of gonadotrophin-releasing hormone antiserum in prepubertal pigs AU - Patton, M. L. AU - Esbenshade, K. L. AU - Flowers, W. L. T2 - Journal of Reproduction & Fertility AB - Summary. Antiserum against gonadotrophin-releasing hormone (GnRH) was infused into one ovary in 4 prepubertal gilts and control porcine serum was infused into one ovary in 4 other gilts. Ovaries were infused for 156 h, after which infused and non-infused ovaries were removed surgically and processed for histology. Infusion of GnRH antibodies did not alter (P > 0·10) concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH) or oestradiol-17β, and GnRH titres in peripheral circulation were low, averaging 1:15. Weights of ovaries not infused were similar (P > 0·10) between treatment groups. There were fewer (P < 0·05) follicles >0·5mm in diameter in the ovaries infused with GnRH antiserum than in the others, but there were no differences (P > 0·10) between treatment groups in the number of follicles < 0·5 mm in diameter. Infusion of GnRH antibodies increased (P < 0·05) the incidence of atresia in follicles with > 4 layers of granulosa cells compared with the other treatment groups. These results provide evidence that a peptide binding to the GnRH antibodies is involved directly in ovarian follicular development. Keywords: GnRH antiserum; follicular development; ovary; pig DA - 1991/// PY - 1991/// DO - 10.1530/jrf.0.0930393 VL - 93 IS - 2 SP - 393 ER - TY - JOUR TI - GENETIC-VARIATION IN REPRODUCTIVE RESPONSES TO A HIGH-ENERGY DIET IN MICE AU - POMP, D AU - EISEN, EJ T2 - JOURNAL OF ANIMAL SCIENCE AB - Effects of a high-energy diet on reproduction were studied in 300 mice from lines selected for litter size and(or) 6-wk BW (L+, increased litter size; W+, increased body weight; L+W-, increased litter size and decreased body weight; L-W+, decreased litter size and increased body weight; and K, randomly selected control). Mice received a high-energy diet (HED; 3.8 kcal/g of ME) or a standard diet (STD; 3.3 kcal/g of ME) from 8 to 11 wk of age and were then mated and evaluated for ovulation rate and embryo survival through 17 d of gestation. The HED increased ovulation rate in all lines (P less than .05). The line x diet interaction was significant, with increased ovulation rate due to HED ranging from 9.9% in W+ to 24.2% in L-W+. Within-line regression coefficients of ovulation rate on ME intake (kilocalories from 10 to 11 wk) varied from .08 +/- .04 (P less than .05) in L+W- to .177 +/- .05 (P less than .01) in L+. In contrast, nonsignificant increases were observed in litter size (live fetuses at 17 d of gestation) due to HED. Effects of HED on embryo survival rate were significantly negative in L+ and L+W-; the decrease in L+ was a result of preimplantation losses, and the decrease in L+W- was due to postimplantation losses. The line x diet interaction was significant for postimplantation embryo survival. The results indicate significant genetic variation in reproductive responses to a high-energy diet in mice. DA - 1991/5// PY - 1991/5// DO - 10.2527/1991.6951875x VL - 69 IS - 5 SP - 1875-1884 SN - 0021-8812 KW - FLUSHING KW - GENETIC VARIATION KW - OVULATION RATE KW - EMBRYO MORTALITY KW - SELECTION KW - MICE ER - TY - JOUR TI - EFFECT OF ACTIVE IMMUNIZATION AGAINST GROWTH HORMONE-RELEASING FACTOR ON GROWTH AND ONSET OF PUBERTY IN BEEF HEIFERS AU - SIMPSON, RB AU - ARMSTRONG, JD AU - HARVEY, RW AU - MILLER, DC AU - HEIMER, EP AU - CAMPBELL, RM T2 - JOURNAL OF ANIMAL SCIENCE AB - Angus and Charolais heifers (195 +/- 7 kg) were actively immunized against growth hormone-releasing factor (GRF) to evaluate the effect on concentrations of somatotropin (ST), insulin-like growth factor I (IGF-I), insulin (INS), growth, and onset of puberty. Primary immunizations were given at 184 +/- 7 d of age (d 0 of experiment) by injecting (s.c.) 1.5 mg of GRF-(1-29)-Gly-Gly-Cys-NH2 conjugated to 1.5 mg of human serum albumin (GRFi, n = 22) or 1.5 mg of human serum albumin (HSAi, n = 21). Booster immunizations of .5 mg of antigen were given on d 62, 92, 153, and 251. Antibody binding (percentage at 1:2,000 dilution) to [125I]GRF on d 69 was greater (P less than .01) in GRFi (53.7 +/- 4.5) than in HSAi (10.1 +/- .6) heifers. Serum concentration (ng/ml) and frequency (peaks/5 h) of ST release, respectively, on d 78 were lower (P less than .01) in GRFi than in HSAi heifers (3.3 +/- .1 vs 5.6 +/- .2 and .9 +/- .3 vs 2.3 +/- .2). Serum IGF-I (ng/ml) was lower (P less than .01) in GRFi than in HSAi heifers on d 69 (41 +/- 5 vs 112 +/- 4). Serum INS (microU/ml) on d 78 was lower (P less than .05) in GRFi (2.2 +/- .1) than in HSAi (3.8 +/- .2) heifers. Feed intake, ADG, and feed efficiency were lower (P less than .05) in GRFi than in HSAi heifers. Hip height was lower (P less than .01) and fat thickness was greater (P less than .05) in GRFi than in HSAi heifers by d 132 and 167, respectively. Percentage of heifers attaining puberty (progesterone greater than 1 ng/ml for two consecutive weeks) by d 209 and 379 (12.9 and 18.5 mo of age), respectively, was lower (P less than .05) in GRFi (40.9 and 45.5) than in HSAi (81.0 and 100). In conclusion, growing heifers were successively immunized against GRF. Active immunization against GRF resulted in decreased serum concentration of ST, IGF-I, and INS. In addition, GRF immunization led to lowered feed intake, ADG, and feed efficiency, increased fat depth, and delayed onset of puberty in heifers. We propose that ST and IGF-I are important metabolic mediators involved in the initiation of puberty in heifers. DA - 1991/12// PY - 1991/12// DO - 10.2527/1991.69124914x VL - 69 IS - 12 SP - 4914-4924 SN - 0021-8812 KW - HEIFER KW - PUBERTY KW - GHRF KW - SOMATOTROPIN KW - IGF-I KW - INSULIN ER - TY - JOUR TI - IMAGE-ANALYSIS AND NONLINEAR MODELING TO DETERMINE DIMENSIONS OF WET-SIEVED, MASTICATED FORAGE PARTICLES AU - LUGINBUHL, JM AU - FISHER, DS AU - POND, KR AU - BURNS, JC T2 - JOURNAL OF ANIMAL SCIENCE AB - A procedure to estimate dimensions of digesta particles was developed and evaluated. After wet sieving, particles of masticated switchgrass and bermudagrass hays retained on sieves with apertures of 1.0 mm2 or larger were placed on moist white filter paper, separated manually, and photographed. Photographs were scanned with a flat-bed scanner, scaled to size, and digitized. Projected area, perimeter, length, and width of particles were determined by a microcomputer system. Variables derived for each particle included the form factor, which was defined as (4 x pi x area)/perimeter2, and each particle's length: width ratio. Ninety-three percent of data from two trials with steers had significant lack of fit (P less than .05 to P less than .0001) to normal, lognormal, Weibull, or gamma distributions. As an alternative, individual particle measurements were summed on a cumulative percentage basis for each variable and were fit to an inverted Gompertz function to estimate median, mode, and mean dimensions of scanned particles. Estimates from the equation fit the distribution well; asymptotic SE averaged 3.5 and 1.4% of parameter means for dimensions of masticated switchgrass and bermudagrass hay particles, respectively. No analytic solution exists for the mean, which must be estimated numerically, but analytic solutions are available for the median and mode. Use of this equation will prevent bias caused by lack of fit to a particular distribution and yield more accurate estimates of mean particle dimensions than arithmetic means. DA - 1991/9// PY - 1991/9// DO - 10.2527/1991.6993807x VL - 69 IS - 9 SP - 3807-3816 SN - 0021-8812 KW - DIMENSIONAL ANALYSIS KW - MASTICATION KW - FORAGE KW - CATTLE ER - TY - JOUR TI - Genetic parameters for testosterone production in boars AU - Lubritz, D. AU - Johnson, B. AU - Robison, O. W. T2 - Journal of Animal Science AB - Data were collected in 1982 through 1989 from 66 sires and 358 Duroc boars. Testosterone production was measured from peripheral blood samples before (PRE) and after (POST) GnRH challenge. Additionally, data were collected on testes length at 168 d (TL168), testes width at 168 d (TW168), testes volume at 168 d (TVOL), birth weight (BWT), average daily gain (ADG), days to 104 kg (DAYS104), and backfat adjusted to 104 kg (FAT). Overall means for these traits were 24.6 ng·ml−1·h−1, 75.7 ng·ml−1·h−1, 12.3 cm, 11.6 cm, 422.0 cm3, 1.5 kg, .5 kg, 189.3 d, and 18.5 mm, respectively. Son-sire regressions were used to calculate genetic parameters. Heritabilities for PRE, POST, TL168, TW168, TVOL, BWT, ADG, DAYS104, and FAT were .37, .26, .33, .34, .33, .21, .42, .35, and 0, respectively. Moderately favorable genetic correlations were obtained for PRE and POST with growth measurements. Large positive genetic correlations were present for both PRE and POST with TL168, TW168, and TVOL, and testes measurements had large positive genetic correlations with growth traits. Selection for testes size or testosterone production should be equally effective. However, it seems that selection for testes size would result in larger changes in measures of growth than selection for testosterone. This study suggests that testes measurements are good predictors of both basal and challenge testosterone levels. Selection for increased testis size or increased testosterone levels would be expected to enhance growth. DA - 1991/// PY - 1991/// DO - 10.2527/1991.6983220x VL - 69 IS - 8 SP - 3220 ER - TY - JOUR TI - Effects of zinc methionine and zinc oxide on performance, blood characteristics, and antibody titer response to viral vaccination in stressed feeder calves AU - Spears, J. W. AU - Harvey, R. W. AU - Brown, T. T., Jr. T2 - Journal of the American Veterinary Medical Association DA - 1991/// PY - 1991/// VL - 199 IS - 12 SP - 1731 ER - TY - JOUR TI - EFFECT OF SELECTION FOR LITTER SIZE AND BODY-WEIGHT ON HORMONE-INDUCED OVULATION RATE IN MICE AU - LUBRITZ, DL AU - EISEN, EJ AU - ROBISON, OW T2 - JOURNAL OF ANIMAL SCIENCE AB - Genetic differences in natural vs hormone-induced ovulation rates were compared in immature female mice from five lines that had undergone long-term single-trait and antagonistic index selection for litter size and(or) 6-wk BW. Lines used were control (K); high litter size (L+); high BW (W+); low litter size and high BW (L-W+); and high litter size and low BW (L+W-). Natural ovulation rate at a mean age of 34.3 d and hormone-induced (5 IU of pregnant mare's serum gonadotropin followed 2 d later by 5 IU of human chorionic gonadotropin) superovulation rate at a fixed age of 31 d were obtained. Total number of eggs ovulated was affected by line (P less than .001), treatment (P less than .001), and line x treatment interaction (P less than .001). Line differences were subsequently tested within treatment because of the significant line x treatment interaction. Line differences were important (P less than .001) for natural ovulation, hormone-induced ovulation, and response to hormones. Mean natural ovulation rates for K, L+, W+, L-W+, and L+W- were 14.1, 19.8, 15.1, 13.6, and 16.4, respectively. Selection changed ovulation rate by 40, 16, 7, and -4% in the L+, L+W-, W+ and L-W+ lines, respectively (P less than .01). Hormone-induced ovulation rates in K, L+, W+, L-W+, and L+W- were 32.3, 24.6, 19.6, 20.9, and 22.1, respectively. Exogenous hormones increased ovulation by 18.2, 4.8, 4.6, 7.3, and 5.7 ova for K, L+, W+, L-W+, and L+W-, respectively (P less than .001). Lines with lower natural ovulation rates had higher responses to superovulation. Increased ovulation rate due to treatment ranged from 24.3% in L+ to 129% in K. These results indicate significant differences among lines in ovarian response to exogenous hormones. DA - 1991/11// PY - 1991/11// DO - 10.2527/1991.69114299x VL - 69 IS - 11 SP - 4299-4305 SN - 0021-8812 KW - SELECTION KW - OVULATION RATE KW - SUPEROVULATION KW - MICE ER - TY - JOUR TI - Milk temperature & teat end pressure detect liner slippage AU - Caruolo, E. V. AU - Vreeland, C. E. AU - Dickey, D. A. T2 - Journal of Dairy Science DA - 1991/// PY - 1991/// VL - 74 SP - 223 ER - TY - JOUR TI - HYPOXIA IN NEONATAL CALVES - EFFECT ON SELECTED METABOLIC PARAMETERS AU - TYLER, H AU - RAMSEY, H T2 - JOURNAL OF DAIRY SCIENCE AB - The effect of reduced oxygen tension in arterial blood (hypoxic hypoxia) for 24 h postpartum on selected metabolic parameters was studied in 12 neonatal calves. During this period, inspired air for hypoxic calves contained 10.5% O2, whereas that for normoxic calves contained 21% O2. After 24 h, inspired air for all calves contained 21% O2. Three dietary treatments also were imposed during the initial 24-h period: colostrum at 0 and 12 h, whole milk at 0 and 12 h, or fasting. All calves were fed colostrum at 24, 36, and 48 h and whole milk at 60 and 72 h. Parameters included plasma glucose, lactate, fructose, and IgG; arterial blood gases; and pH. Arterial partial pressure of oxygen was maintained near 25 mm Hg throughout the period of hypoxia. Arterial partial pressure of carbon dioxide was unchanged during the period of hypoxia (approximately 45 mm Hg) but was lower (39 mm Hg) in posthypoxic calves. Glucose tended to be lower in hypoxic calves; however, this difference was not statistically significant. Hypoxic calves had significantly higher plasma lactate concentrations contributing to a progressive primary metabolic acidosis. DA - 1991/6// PY - 1991/6// DO - 10.3168/jds.S0022-0302(91)78362-8 VL - 74 IS - 6 SP - 1957-1962 SN - 0022-0302 ER - TY - JOUR TI - HYPOXIA IN NEONATAL CALVES - EFFECT ON INTESTINAL TRANSPORT OF IMMUNOGLOBULINS AU - TYLER, H AU - RAMSEY, H T2 - JOURNAL OF DAIRY SCIENCE AB - The effect of reduced oxygen tension in arterial blood (hypoxic hypoxia) for 24 h postpartum on the absorption of colostral Ig was studied in 12 neonatal calves. During this period, inspired air for hypoxic calves contained 10.5% O2, whereas that for normoxic calves contained 21% O2. After 24 h, inspired air for all calves contained 21% O2. Three dietary regimens also were imposed during the initial 24-h period: colostrum at 0 and 12 h, whole milk at 0 and 12 h, or fasting. Colostrum was fed to all calves at 24, 36, and 48 h. During the initial 24-h period, means for arterial partial pressure of oxygen were 26 and 73 mm Hg for hypoxic and normoxic calves, respectively. In those fed colostrum at 0 and 12 h, hypoxia extended the period of Ig absorption from 20 to 40.5 h. In calves fed whole milk or those that were fasted, no such effect was noted. These observations suggest that the effect of hypoxia on the cessation of Ig absorption by the small intestine is mediated through a secondary and as yet undetermined mechanism. DA - 1991/6// PY - 1991/6// DO - 10.3168/jds.S0022-0302(91)78361-6 VL - 74 IS - 6 SP - 1953-1956 SN - 0022-0302 KW - CALVES KW - IMMUNOGLOBULINS KW - HYPOXIA ER - TY - JOUR TI - Effects of grass species on growing steers: II. Dry matter intake and digesta kinetics AU - Burns, J. C. AU - Pond, K. R. AU - Fisher, D. S. T2 - Journal of Animal Science AB - Animal responses to treatments in grazing experiments frequently remain unexplained because of inadequate pasture and(or) animal measurements. This 2-yr study examined DMI, gastrointestinal tract fill of undigested DM (FILL), rate of digesta passage (ROP), and digesta mean retention time (MRT) for steers grazing tall fescue (Festuca arundinacea Schreb.), switchgrass (Panicum virgatum L.), flaccidgrass (Pennisetum flaccidum Griseb.), and bermudagrass (Cynodon dactylon [L.] Pers.). A randomized complete block design was used with two agronomic replicates. Comparisons in June (yr 1) among continuously grazed switchgrass (SG), flaccidgrass (FG), and bermudagrass (BG) or in May (yr 2) among tall fescue (TF), SG, and FG showed similar digesta kinetics, but different DMI (kg.d-1.100 kg BW-1), among these forages within each sampling. In the June evaluation, the DMI of SG and FG were similar (means = 3.09), DMI of bermudagrass (BG) was lowest (2.23), and fecal DM output (FO) was similar among forages. In the May evaluation, DMI by steers grazing SG (3.90) was higher than that by steers grazing FG (2.97); DMI of tall fescue (TF) was intermediate (3.41) but similar to DMI of FG. Differences in DMI were due to differences in diet in vitro DM disappearance (IVDMD) rather than to differences in digesta kinetics. In July (yr 2), the MRT was highest for BG (84 h) and similar for SG and FG (57 h). Steers grazing different forages exhibited similar ROP and FILL, but FO (kg.d-1.100 kg BW-1) among steers varied (.37 for steers fed BG; .74 for steers fed SG and FG).(ABSTRACT TRUNCATED AT 250 WORDS) DA - 1991/// PY - 1991/// DO - 10.2527/1991.6931199x VL - 69 IS - 3 SP - 1199 ER - TY - JOUR TI - Changes in growth hormone and luteinizing hormone following acute or chronic administration of an opioid agonist, FK33-824, in wethers AU - Armstrong, J. D. AU - Spears, J. W. T2 - Journal of Animal Science AB - Two experiments were conducted to determine the effect of acute or chronic administration of an opioid agonist, (D-Ak2, MePhe4, Met(0)5-ol)-enkephalin (FK33-824), on concentrations of growth hormone (GH) and LH in castrate sheep (wethers). In Exp. 1, we evaluated the effect of acute administration (two injections or infusion for 2 h) of FK33-824 on GH and LH. Wethers (31 ± 1 kg; n = 12) received FK33-824 or saline via one of the three following routes of delivery: 1) i.v. (8 µg/kg) at 0 and 60 min (i.v., n = 4), 2) s.c. (16 µg/kg) at 0 and 60 min (s.c., n = 4), or 3) i.v. infusion (8 µg•kg−1•h−1) for 120 min (inf., n = 4) preceded by a single injection (8 µg/kg). Wethers received FK33-824 and saline on d 1 and 2 or d 2 and 1, respectively. Concentrations of GH were consistently elevated (P < .05) by FK33-824 regardless of route of delivery. Infusion of FK33-824 for 120 min maintained GH concentrations greater (P < .05) than pretreatment or those during infusion of saline. Average LH was decreased consistently by FK33-824, independent of its route of administration; episodic release of LH was suppressed. In Exp. 2, crossbred wethers (36 ± 2 kg; n = 12) were used to determine the effect of chronic administration (s.c.) of FK33-824 on the concentrations of GH and LH and retention of N and energy.(ABSTRACT TRUNCATED AT 250 WORDS) DA - 1991/// PY - 1991/// DO - 10.2527/1991.692774x VL - 69 IS - 2 SP - 774 ER - TY - JOUR TI - Air leakage and milking rate relationships AU - Caruolo, E. V. AU - Vreeland, C. E. AU - Dickey, D. A. T2 - Journal of Dairy Science DA - 1991/// PY - 1991/// VL - 74 SP - 222 ER - TY - JOUR TI - Use of in vitro fertilization and embryo transfer to circumvent infertility caused by an inherited imperforate vagina in mice AU - Didion, B. A. AU - Hauser, M. E. AU - Eisen, E. J. T2 - Journal of In Vitro Fertilization and Embryo Transfer DA - 1991/// PY - 1991/// DO - 10.1007/BF01131709 VL - 8 IS - 3 SP - 167 ER - TY - JOUR TI - ROLES OF ESTRADIOL AND GONADOTROPIN-RELEASING-HORMONE IN CONTROLLING NEGATIVE AND POSITIVE FEEDBACK ASSOCIATED WITH THE LUTEINIZING-HORMONE SURGE IN OVARIECTOMIZED PIGS AU - BRITT, JH AU - ESBENSHADE, KL AU - ZIECIK, AJ T2 - BIOLOGY OF REPRODUCTION AB - Ovariectomized gilts (n = 63) were given estradiol benzoate (estradiol), antiserum to neutralize endogenous GnRH, and pulses of a GnRH agonist (GnRH-A) to stimulate release of LH. GnRH-A was given as 200-ng pulses hourly from 0 to 54 h and as 100- or 200-ng pulses every 30 or 60 min from 54 to 96 h after estradiol. Estradiol alone suppressed LH from 6 to 54 h and elicited an LH surge that peaked at 72 h. When GnRH-A was given every 30–60 min from 0 to 96 h, estradiol suppressed LH for 6–12 h, but then LH returned to pre-estradiol concentrations. When pulses of GnRH-A were given only between 54 and 96 h after estradiol, the surge of LH was related positively to dose and frequency of GnRH-A. We conclude that 1) estrogen acts at the hypothalamus to inhibit release of GnRH for 54 h and then causes a synchronous release of GnRH; 2) estrogen acts at the pituitary to block its response to GnRH for 6–12 h and enhances the accumulation of releasable LH; and 3) magnitude of the LH surge is dependent on the amount of GnRH stimulation. DA - 1991/9// PY - 1991/9// DO - 10.1095/biolreprod45.3.478 VL - 45 IS - 3 SP - 478-485 SN - 0006-3363 ER - TY - JOUR TI - Maximizing fertility and fecundity in the sow AU - Britt, J. H. AU - Sesti, L. A. C. T2 - Revista Brasileira de Reproducao Animal DA - 1991/// PY - 1991/// IS - 3 SP - 22 ER - TY - JOUR TI - MORPHOLOGICAL ABNORMALITIES, NEONATAL-MORTALITY, AND REPRODUCTIVE ABNORMALITIES IN MICE TRANSGENIC FOR DIPHTHERIA-TOXIN GENES THAT ARE DRIVEN BY THE PROMOTER FOR ADIPOCYTE LIPID-BINDING PROTEIN AU - HOMANICS, GE T2 - DEVELOPMENTAL GENETICS AB - Abstract Transgenic mice were used in an experiment that was designed to serve as a model of a possible approach to reducing the amount of carcass fat in meat animals. The objective was to reduce the number of adipocytes in transgenic mice thereby restricting the capacity to accumulate lipid. Our approach employed the technique of genetic ablation. The promoter for the adipocyte lipid binding protein gene was used in an attempt to direct expression of diphtheria toxin genes specifically to adipocytes. Three diphtheria toxin genes were used; they encode, respectively, an extremely cytotoxic wild type toxin, a less toxic attenuated toxin, and a nonfunctional toxin. While it was not possible to accurately assess effects of the transgenes on lipid accumulation, several informative observations were noted. A large percentage of transgenic founder mice that harbor either wild type or attenuated toxin genes are morphologically abnormal, die as neonates, or exhibit reproductive abnormalities including sterility or failure to transmit the transgene to offspring. In contrast, mice that harbor the nonfunctional toxin gene or are nontransgenic rarely have these same abnormalities. These results suggest that the trans‐genic mice are expressing the transgenes in cells other than adipocytes and that the aberrant production of functional toxin is responsible for the congenital abnormalities. The production of morphological and reproductive abnormalities in transgenic animals should be useful for investigating normal developmental processes. DA - 1991/// PY - 1991/// DO - 10.1002/dvg.1020120506 VL - 12 IS - 5 SP - 371-379 SN - 0192-253X KW - GENETIC ABLATION KW - CONGENITAL ABNORMALITIES KW - TRANSGENIC MICE KW - CELL DEATH ER - TY - JOUR TI - NUTRITIONAL, PHYSIOLOGICAL, GENETIC, SEX, AND AGE EFFECTS ON FAT-FREE DRY-MATTER COMPOSITION OF THE BODY IN AVIAN, FISH, AND MAMMALIAN-SPECIES - A REVIEW AU - CLAWSON, AJ AU - GARLICH, JD AU - COFFEY, MT AU - POND, WG T2 - JOURNAL OF ANIMAL SCIENCE AB - The purpose of this review is to outline and interpret the effects of nutrition, physiological state, sex, genetics, and age on composition of the fat-free dry matter of birds, mammals, and fishes in order to test the hypothesis that the protein:ash ratio in the body is constant. Calculations from a broad array of published data revealed that nutritional factors, including mineral, protein and amino acid nutriture, frequency and level of feeding, and energy intake and nonnutritional factors, including physiological state, sex, genetic background, and age of animal, may each alter the ratio of protein:ash in the body. All or part of the response may be associated with changes in accretion of body protein and(or) skeletal development and mineralization imposed by these nutritional and nonnutritional factors. In most cases of amino acid or protein deficiency, the protein:ash ratio was decreased relative to the control because the deposition of protein in muscle and viscera was reduced more than the growth and mineralization of the skeleton. In other cases, the protein:ash ratio was increased relative to a control because the dietary Ca or P intake or absorption limited skeletal mineralization. More knowledge is needed of how skeletal development and protein:ash ratio in the body is regulated, especially under the influence of nutritional, ontogenetic, and physiological variables among different genotypes of mammals, birds, and fishes. Documentation that the protein:ash ratio in the whole body of representative mammals, birds, and fishes is not constant, but is subject to manipulation, has important physiological and economic implications for developing food animals for the efficient production of lean meat. DA - 1991/9// PY - 1991/9// DO - 10.2527/1991.6993617x VL - 69 IS - 9 SP - 3617-3644 SN - 1525-3163 KW - BODY COMPOSITION KW - PROTEIN CONTENT KW - ASH CONTENT KW - NUTRITIONAL STATE KW - PHYSIOLOGICAL STATE KW - GENETIC EFFECTS ER - TY - JOUR TI - METABOLIC RESPONSES TO PROTEIN SUPPLEMENTATION AND SLAFRAMINE IN GOATS AND SHEEP FED ROUGHAGE AU - GASKINS, HR AU - CROOM, WJ AU - FERNANDEZ, JM AU - VANEYS, JE AU - HAGLER, WM AU - JOHNSON, WL T2 - SMALL RUMINANT RESEARCH AB - Eighteen grade Angora goats (BW 14 kg) and 18 Barbados Blackbelly × Dorset sheep (BW 24 kg), all wethers, were fed coastal bermudagrass hay (84% neutral detergent fiber, 6% crude protein) supplemented with alfalfa hay or cotton seed meal during an 84-day feeding trial. On day 28, daily treatment with slaframine (SF; 30 μg kg−1 BW), a parasympathomimetic with high affinity for the gastrointestinal tract, or physiological saline was initiated. On day 70, blood samples were obtained at hourly intervals for analyses of glucose (GLU), nonesterified fatty acids (NEFA), urea nitrogen (PUN), insulin (INS), glucagon (GLN), thyroxine (T4), and triiodothyronine uptake (T3U). Plasma concentrations of GLU, NEFA and PUN did not differ between species. Goats had higher (P < 0.05) concentrations of INS, T3, and lower percentage T3U than sheep. The INS to GLN ratio (I/G), was also greater (P < 0.05) in goats. SF increased (P < 0.05) GLU and NEFA and decreased (P < 0.01) PUN. INS tended to decrease and GLN to increase in response to SF, resulting in a lower (P < 0.05) I/G. SF increased (P < 0.05) T4 concentrations and lowered (P < 0.05) the percentage T3U. Protein supplementation increased (P < 0.01) PUN concentrations without affecting plasma concentrations of GLU and NEFA. Plasma concentrations of INS and GLN did not change in response to protein supplementation, while metabolite and hormonal changes were minimal, but SF administration resulted in major changes in blood metabolite and hormone profiles. DA - 1991/10// PY - 1991/10// DO - 10.1016/0921-4488(91)90010-N VL - 6 IS - 1-2 SP - 73-84 SN - 0921-4488 ER - TY - JOUR TI - EFFECTS OF PRETREATMENT WITH ADRENOCORTICOTROPIN ON ENDOCRINE AND BEHAVIORAL-RESPONSES OF BULLS TO SEXUAL-ACTIVITY AU - BORG, KE AU - ESBENSHADE, KL AU - JOHNSON, BH T2 - THERIOGENOLOGY AB - Peripheral concentrations of cortisol, growth hormone and testosterone were determined in two experiments which examined the endocrine and behavioral responses of sexually mature Angus bulls to an estrous female (Experiment 1) and to female exposure 5 hours following an adrenocorticotropin (ACTH) injection (Experiment 2). Sexual activity of bulls in Experiment 1 significantly increased levels of cortisol when compared with concentrations before exposure to a female. Administration of ACTH in Experiment 2 consistently elevated levels of cortisol by 30-fold (P<0.01) when compared with pre-ACTH concentrations. This heightened level of cortisol persisted throughout the period of exposure to an estrous cow, although a gradual decline in cortisol concentrations occurred over time (P<0.05). In Experiment 1, growth hormone profiles tended to increase in response to sexual activity (P<0.10), whereas in Experiment 2, growth hormone increased in response to ACTH administration (P<0.01) and to female exposure (P<0.01). Concentrations of testosterone were unaffected (P>0.10) by mating activity in Experiment 1. In Experiment 2, acute suppression (P<0.01) in testosterone concentrations 5 hours after ACTH administration coincided with the exposure period to the estrous female. Frequencies of mounting behavious (penis extension, mounting, intromission and ejaculation) exhibited by ACTH-treated bulls were significantly lower compared with the frequencies two days earlier. Exogenous ACTH administration suppressed reproductive behaviors of bulls and altered secretion of cortisol, growth hormone and testosterone. Furthermore, these data provide evidence that specific mating behaviors of the bull can be influenced by circulating steroids. DA - 1991/10// PY - 1991/10// DO - 10.1016/0093-691X(91)90398-W VL - 36 IS - 4 SP - 607-618 SN - 1879-3231 KW - BULLS KW - ACTH KW - HORMONES KW - SEXUAL BEHAVIOR ER - TY - JOUR TI - Cortisol, growth hormone, and testosterone concentrations during mating behavior in the bull and boar AU - Borg, K. E. AU - Esbenshade, K. L. AU - Johnson, B. H. T2 - Journal of Animal Science AB - Two experiments were conducted to evaluate peripheral concentrations of Cortisol (C), growth hormone (GH), and testosterone (T) in bulls and boars during mating and to correlate mating behaviors with endocrine secretion in the presence of an estrous female. In Exp. 1, six sexually inexperienced mature bulls were bled every 15 min for 2 h before and 2 h after a 30-min exposure to a single, restrained, estrous cow; sampling occurred every 5 min during exposure. In Exp. 2, six sexually experienced boars were bled similarly before and after exposure to a sow and every 5 min during a 15-min exposure to a freely moving, estrous sow. Behavioral events recorded during exposure to a female included the following: flehmen responses (bulls only), mounts, penis extensions, intromissions, ejaculations, and time to first mount and first ejaculation. Of the six bulls, four completed at least one service (intromission + ejaculation), and three of six mounted the estrous cow eight or more times. Completion of one or more services resulted in significant elevations in serum C and GH concentrations, but not T concentrations, during the exposure period. Bulls mounting eight or more times also experienced significant elevations in C concentrations during exposure. Three of six boars completed at least one service. Servicing and mounting the sow fewer than five times were both associated with significant elevations in serum C concentrations. Serum concentrations of T were also elevated as a result of exposure to an estrous sow. Collectively, these data support the suggestion that specific events during natural mating activity can alter endocrine secretions of C and GH in bulls and C and T in boars. DA - 1991/// PY - 1991/// DO - 10.2527/1991.6983230x VL - 69 IS - 8 SP - 3230 ER - TY - JOUR TI - CARNITINE STATUS AND LIPID UTILIZATION IN NEONATAL PIGLETS FED DIETS LOW IN CARNITINE AU - COFFEY, MT AU - SHIREMAN, RB AU - HERMAN, DL AU - JONES, EE T2 - JOURNAL OF NUTRITION AB - Forty-eight newborn piglets were assigned to dietary regimens to examine carnitine status and lipid utilization by piglets nursing sows (Diet 1), fed a high-carnitine (1507 µmol camitine/kg dry matter) caseinwhey formula (Diet 2) or fed a low-carnitine (35 µmol carnitine/kg dry matter) egg white protein formula (Diet 3). Four piglets were killed at birth, and four per dietary group were killed at 3, 7, 14 and 21 d of age. Piglets fed Diet 3 had lower (P < 0.01) carnitine in plasma and liver by d 7 and carnitine remained lower to d 21. Heart carnitine tended to be lower in piglets fed Diet 3, but the differences were not significant. Longissimus muscle carnitine was not affected. In vitro palmitate oxidation was lower (P < 0.05) on d 7 in the liver from piglets fed Diet 3 but not on d 3, 14 and 21. Low dietary carnitine did not affect in vitro liver β-hydroxybutyrate production or oxidation of palmitate by longissimus muscle. Plasma glucose and nonesterified fatty acids were higher (P < 0.05) in piglets nursing sows than those fed Diets 2 or 3. Piglets receiving Diet 3 had reduced carnitine in plasma and certain tissues, and liver lipid oxidation was depressed on d 7 of age, compared with those receiving the other two diets. Feeding the low carnitine diet did not alter glucose status or plasma lipids and ketones. DA - 1991/7// PY - 1991/7// DO - 10.1093/jn/121.7.1047 VL - 121 IS - 7 SP - 1047-1053 SN - 1541-6100 KW - CARNITINE KW - PORCINE KW - NEONATE KW - LIPID UTILIZATION KW - PIGS ER - TY - JOUR TI - PASSIVE-IMMUNIZATION OF THE PIG AGAINST GONADOTROPIN-RELEASING-HORMONE DURING THE FOLLICULAR PHASE OF THE ESTROUS-CYCLE AU - ESBENSHADE, KL T2 - THERIOGENOLOGY AB - Three experiments were conducted to determine the effects of passively immunizing pigs against gonadotropin releasing hormone (GnRH) during the follicular phase of the estrous cycle. In Experiment 1, sows were given GnRH antibodies at weaning and they lacked estrogen secretion during the five days immediately after weaning and had delayed returns to estrus. In Experiment 2, gilts passively immunized against GnRH on Day 16 or 17 of the estrous cycle (Day 0 = first day of estrus) had lower (P<0.03) concentrations of estradiol-17beta than control gilts, and they did not exhibited estrus at the expected time (Days 18 to 22). When observed three weeks after passive immunization, control gilts had corpora lutea present on their ovaries, whereas GnRH-immunized gilts had follicles and no corpora lutea. The amount of GnRH antiserum given did not alter (P<0.05) serum concentrations of LH or pulsatile release of LH in sows and gilts. In Experiment 3, prepuberal gilts were given 1,000 IU PMSG at 0 h and GnRH antiserum at 72 and 120 h. This treatment lowered the preovulatory surge of LH and FSH, but it did not alter serum estradiol-17beta concentrations, the proportion of pigs exhibiting estrus, or the ovulation rate. These results indicate that passive immunization of pigs against GnRH before initiation of or during the early part of the follicular phase of the estrous cycle retards follicular development, whereas administration of GnRH antibodies during the latter stages of follicular development does not have an affect. Since the concentration of antibodies was not high enough to alter basal or pulsatile LH secretion, the mechanism of action of the GnRH antiserum may involve a direct ovarian action. DA - 1991/5// PY - 1991/5// DO - 10.1016/0093-691X(91)90299-S VL - 35 IS - 5 SP - 869-881 SN - 0093-691X KW - PIG KW - GNRH KW - IMMUNIZATION KW - ESTROUS CYCLE ER - TY - JOUR TI - Effects of human chorionic gonadotrophin on contractile activity of steroid-primed pig myometrium in vitro AU - Flowers, B. AU - Ziecik, A. J. AU - Caruolo, E. V. T2 - Journal of Reproduction & Fertility AB - We examined the effects of (a) oestrogen and progesterone on concentrations of luteinizing hormone/human chorionic gonadotrophin (LH/hCG) receptors in uterine smooth muscle in vivo and (b) hCG on spontaneous myometrial contractions in vitro. Ovariectomized gilts received 2 ml corn oil (control; n = 5), 2 mg oestradiol benzoate (n = 6) or 20 mg progesterone (n = 5) for 5 days. Gilts were hysterectomized 8 h after the last injection and longitudinal sections of myometrium were incubated in modified Krebs' solution with 0 or 10 i.u. of hCG (n = 10/gilt) for 4 h at 37 degrees C in 95% O2:5% CO2. After incubation, myometrial sections were placed in a tissue chamber perfused with Krebs' solution and mechanical activity was recorded for 30 min. Cell membrane fractions were prepared from myometrial tissue not used for in-vitro studies and analysed for LH/hCG receptors. Treatment with oestradiol benzoate increased (P less than 0.01) the number of LH/hCG-binding sites compared with gilts receiving corn oil or progesterone. Incubation of myometrium with hCG reduced (P less than 0.01) the frequency and amplitude of spontaneous uterine contractions in gilts treated with oestradiol benzoate. In contrast, hCG had no effect (P greater than 0.05) on the pattern of myometrial contractions in gilts given corn oil or progesterone. These results indicate that oestradiol promotes the synthesis of LH/hCG receptors in pig myometrium and incubation of oestrogen-primed tissue with hCG has a quiescent effect on myometrial contractility. DA - 1991/// PY - 1991/// DO - 10.1530/jrf.0.0920425 VL - 92 IS - 2 SP - 425 ER - TY - JOUR TI - Effect of insulin-like growth factor-I on protein synthesis in porcine embryonic discs cultured in vitro AU - Estrada, J. L. AU - Jones, E. E. AU - Johnson, B. H. AU - Petters, R. M. T2 - Journal of Reproduction & Fertility AB - Porcine embryos at Day 13 (Day 0 = first day of oestrus) were collected surgically and embryonic discs were isolated microsurgically. The discs were washed and cultured in Dulbecco's modified Eagle's medium without serum, with either 14C-leucine alone or 14C-leucine plus insulin-like growth factor-I (IGF-I) (100 ng/ml) at 37 degrees C for 48 h in 5% CO2 in air. After incubation, discs were morphologically evaluated, frozen in liquid nitrogen and stored at -70 degrees C. No statistical differences in morphology were observed between embryonic discs cultured in medium with IGF-I and those cultured in medium alone (control). Although more radioactivity was incorporated by embryonic discs in the presence of IGF-I than by those cultured in medium without the growth factor, the difference between the two groups was not significant. From two-dimensional gel electrophoresis, it was observed that IGF-I selectively stimulated the synthesis of four new proteins with Mr of 24,000, 70,000, 77,000 and 95,000, respectively and pI between 5.5 and 6.5. At least 90% of the other proteins in the gels was synthesized in greater amount by embryonic discs cultured in the presence of IGF-I than in the controls. These results show that IGF-I can stimulate protein synthesis in pig embryonic discs cultured in vitro and suggest that this growth factor may play an important role in regulating early development. DA - 1991/// PY - 1991/// DO - 10.1530/jrf.0.0930053 VL - 93 IS - 1 SP - 53 ER - TY - JOUR TI - Effect of infusion of arginine or branch chain amino acids in early lactation Holstein dairy cows fed corn silage AU - Daniel, T. E. AU - Rakes, A. H. AU - Zimmerman, C. A. AU - Hopkins, B. A. T2 - Journal of Dairy Science DA - 1991/// PY - 1991/// VL - 74 SP - 182 ER - TY - PAT TI - Method of degrading keratinaceous material and bacteria useful therefor AU - Shih, J. C. H. AU - Williams, C. M. C2 - 1991/// DA - 1991/// PY - 1991/// ER -